Buggy code:
this . insert_new_line_in_empty_type_declaration = true ; this . insert_space_after_and_in_type_parameter = true ; this . insert_space_after_assignment_operator = true ; this . insert_space_after_at_in_annotation = false ; this . insert_space_after_at_in_annotation_type_declaration = false ; this . insert_space_after_binary_operator = true ; this . insert_space_after_closing_angle_bracket_in_type_arguments = true ; this . insert_space_after_closing_angle_bracket_in_type_parameters = true ; this . insert_space_after_closing_paren_in_cast = true ; this . insert_space_after_closing_brace_in_block = true ; this . insert_space_after_colon_in_assert = true ; this . insert_space_after_colon_in_case = true ; this . insert_space_after_colon_in_conditional = true ; this . insert_space_after_colon_in_for = true ; this . insert_space_after_colon_in_labeled_statement = true ; this . insert_space_after_comma_in_allocation_expression = true ; this . insert_space_after_comma_in_annotation = true ; this . insert_space_after_comma_in_array_initializer = true ; this . insert_space_after_comma_in_constructor_declaration_parameters = true ; this . insert_space_after_comma_in_constructor_declaration_throws = true ; this . insert_space_after_comma_in_enum_constant_arguments = true ; this . insert_space_after_comma_in_enum_declarations = true ; this . insert_space_after_comma_in_explicit_constructor_call_arguments = true ; this . insert_space_after_comma_in_for_increments = true ; this . insert_space_after_comma_in_for_inits = true ; this . insert_space_after_comma_in_method_invocation_arguments = true ; this . insert_space_after_comma_in_method_declaration_parameters = true ; this . insert_space_after_comma_in_method_declaration_throws = true ; this . insert_space_after_comma_in_multiple_field_declarations = true ; this . insert_space_after_comma_in_multiple_local_declarations = true ; this . insert_space_after_comma_in_parameterized_type_reference = true ; this . insert_space_after_comma_in_superinterfaces = true ; this . insert_space_after_comma_in_type_arguments = true ; this . insert_space_after_comma_in_type_parameters = true ; this . insert_space_after_ellipsis = true ; this . insert_space_after_opening_angle_bracket_in_parameterized_type_reference = false ; this . insert_space_after_opening_angle_bracket_in_type_arguments = false ; this . insert_space_after_opening_angle_bracket_in_type_parameters = false ; this . insert_space_after_opening_bracket_in_array_allocation_expression = false ; this . insert_space_after_opening_bracket_in_array_reference = false ; this . insert_space_after_opening_brace_in_array_initializer = true ; this . insert_space_after_opening_paren_in_annotation = false ; this . insert_space_after_opening_paren_in_cast = false ; this . insert_space_after_opening_paren_in_catch = false ; this . insert_space_after_opening_paren_in_constructor_declaration = false ; this . insert_space_after_opening_paren_in_enum_constant = false ; this . insert_space_after_opening_paren_in_for = false ; this . insert_space_after_opening_paren_in_if = false ; this . insert_space_after_opening_paren_in_method_declaration = false ; this . insert_space_after_opening_paren_in_method_invocation = false ; this . insert_space_after_opening_paren_in_parenthesized_expression = false ; this . insert_space_after_opening_paren_in_switch = false ; this . insert_space_after_opening_paren_in_synchronized = false ; this . insert_space_after_opening_paren_in_while = false ; this . insert_space_after_postfix_operator = false ; this . insert_space_after_prefix_operator = false ; this . insert_space_after_question_in_conditional = true ; this . insert_space_after_question_in_wilcard = false ; this . insert_space_after_semicolon_in_for = true ; this . insert_space_after_unary_operator = false ; this . insert_space_before_and_in_type_parameter = true ; this . insert_space_before_at_in_annotation_type_declaration = true ; this . insert_space_before_assignment_operator = true ; this . insert_space_before_binary_operator = true ; this . insert_space_before_closing_angle_bracket_in_parameterized_type_reference = false ; this . insert_space_before_closing_angle_bracket_in_type_arguments = false ; this . insert_space_before_closing_angle_bracket_in_type_parameters = false ; this . insert_space_before_closing_brace_in_array_initializer = true ; this . insert_space_before_closing_bracket_in_array_allocation_expression = false ; this . insert_space_before_closing_bracket_in_array_reference = false ; this . insert_space_before_closing_paren_in_annotation = false ; this . insert_space_before_closing_paren_in_cast = false ; this . insert_space_before_closing_paren_in_catch = false ; this . insert_space_before_closing_paren_in_constructor_declaration = false ; this . insert_space_before_closing_paren_in_enum_constant = false ; this . insert_space_before_closing_paren_in_for = false ; this . insert_space_before_closing_paren_in_if = false ; this . insert_space_before_closing_paren_in_method_declaration = false ; this . insert_space_before_closing_paren_in_method_invocation = false ; this . insert_space_before_closing_paren_in_parenthesized_expression = false ; this . insert_space_before_closing_paren_in_switch = false ; this . insert_space_before_closing_paren_in_synchronized = false ; this . insert_space_before_closing_paren_in_while = false ; this . insert_space_before_colon_in_assert = true ; this . insert_space_before_colon_in_case = false ; this . insert_space_before_colon_in_conditional = true ; this . insert_space_before_colon_in_default = false ; this . insert_space_before_colon_in_for = true ; this . insert_space_before_colon_in_labeled_statement = false ; this . insert_space_before_comma_in_allocation_expression = false ; this . insert_space_before_comma_in_array_initializer = false ; this . insert_space_before_comma_in_constructor_declaration_parameters = false ; this . insert_space_before_comma_in_constructor_declaration_throws = false ; this . insert_space_before_comma_in_enum_constant_arguments = false ; this . insert_space_before_comma_in_enum_declarations = false ; this . insert_space_before_comma_in_explicit_constructor_call_arguments = false ; this . insert_space_before_comma_in_for_increments = false ; this . insert_space_before_comma_in_for_inits = false ; this . insert_space_before_comma_in_method_invocation_arguments = false ; this . insert_space_before_comma_in_method_declaration_parameters = false ; this . insert_space_before_comma_in_method_declaration_throws = false ; this . insert_space_before_comma_in_multiple_field_declarations = false ; this . insert_space_before_comma_in_multiple_local_declarations = false ; this . insert_space_before_comma_in_parameterized_type_reference = false ; this . insert_space_before_comma_in_superinterfaces = false ; this . insert_space_before_comma_in_type_arguments = false ; this . insert_space_before_comma_in_type_parameters = false ; this . insert_space_before_ellipsis = false ; this . insert_space_before_parenthesized_expression_in_return = true ; this . insert_space_before_opening_angle_bracket_in_parameterized_type_reference = false ; this . insert_space_before_opening_angle_bracket_in_type_arguments = false ; this . insert_space_before_opening_angle_bracket_in_type_parameters = false ; this . insert_space_before_opening_brace_in_annotation_type_declaration = true ; this . insert_space_before_opening_brace_in_anonymous_type_declaration = true ; this . insert_space_before_opening_brace_in_array_initializer = true ; this . insert_space_before_opening_brace_in_block = true ; this . insert_space_before_opening_brace_in_constructor_declaration = true ; this . insert_space_before_opening_brace_in_enum_constant = true ; this . insert_space_before_opening_brace_in_enum_declaration = true ; this . insert_space_before_opening_brace_in_method_declaration = true ; this . insert_space_before_opening_brace_in_switch = true ; this . insert_space_before_opening_brace_in_type_declaration = true ; this . insert_space_before_opening_bracket_in_array_allocation_expression = false ; this . insert_space_before_opening_bracket_in_array_reference = false ; this . insert_space_before_opening_bracket_in_array_type_reference = false ; this . insert_space_before_opening_paren_in_annotation = false ; this . insert_space_before_opening_paren_in_annotation_type_member_declaration = false ; this . insert_space_before_opening_paren_in_catch = true ; this . insert_space_before_opening_paren_in_constructor_declaration = false ; this . insert_space_before_opening_paren_in_enum_constant = false ; this . insert_space_before_opening_paren_in_for = true ; this . insert_space_before_opening_paren_in_if = true ; this . insert_space_before_opening_paren_in_method_invocation = false ; this . insert_space_before_opening_paren_in_method_declaration = false ; this . insert_space_before_opening_paren_in_switch = true ; this . insert_space_before_opening_paren_in_synchronized = true ; this . insert_space_before_opening_paren_in_parenthesized_expression = false ; this . insert_space_before_opening_paren_in_while = true ; this . insert_space_before_postfix_operator = false ; this . insert_space_before_prefix_operator = false ; this . insert_space_before_question_in_conditional = true ; this . insert_space_before_question_in_wilcard = false ; this . insert_space_before_semicolon = false ; this . insert_space_before_semicolon_in_for = false ; this . insert_space_before_unary_operator = false ; this . insert_space_between_brackets_in_array_type_reference = false ; this . insert_space_between_empty_braces_in_array_initializer = false ; this . insert_space_between_empty_brackets_in_array_allocation_expression = false ; this . insert_space_between_empty_parens_in_annotation_type_member_declaration = false ; this . insert_space_between_empty_parens_in_constructor_declaration = false ; this . insert_space_between_empty_parens_in_enum_constant = false ; this . insert_space_between_empty_parens_in_method_declaration = false ; this . insert_space_between_empty_parens_in_method_invocation = false ; this . compact_else_if = true ; this . keep_guardian_clause_on_one_line = false ; this . keep_else_statement_on_same_line = false ; this . keep_empty_array_initializer_on_one_line = false ; this . keep_simple_if_on_one_line = false ; this . keep_then_statement_on_same_line = false ; this . number_of_empty_lines_to_preserve = 1 ; this . put_empty_statement_on_new_line = true ; this . tab_size = 8 ; this . page_width = 80 ; <START_BUG> this . tab_char = DefaultCodeFormatterOptions . SPACE ; <END_BUG> this . use_tabs_only_for_leading_indentations = false ; } }

Fix:
this . tab_char = DefaultCodeFormatterOptions . MIXED ;